Wideband planar circularly polarized antenna and antenna device

摘要

A planar antenna includes a patch conductor formed on a front surface of a dielectric substrate 20 so to be obliquely arranged in relation to an orthogonal axis of the dielectric substrate, the patch conductor having an elliptic shape; a microstrip line 40 for feeding power to a bottom part of the patch conductor; and a ground conductor plate 50 formed on a back surface of the dielectric substrate at a position thereof that is not overlapped with the patch conductor. By forming the patch conductor to be inclined only by θ, circular polarization characteristics in which axial ratio is 3 dB or less are given and the wideband such that the frequency bandwidth in which VSWR characteristics are 2 or less is 2 through 5 GHz and the wideband in UWB High band can be attained. The antenna characteristics in which any radiation directivity on the zenith direction does not depend on the frequency are obtained.